Sofa-bed assembly



May 30, 1967 POKORNY, JR

SOFA-BED AS SEMBLY 5 Sheets-Sheet 1 Filed Dec. 1, 1964 K m E V m 100/6 Po/vo/pwde BY W I L. POKORNY, JR

May 30, 1967 1 SOFA-BED ASSEMBLY 5 Sheets-Sheet 3 Filed Dec. '1, 1964 INVENTOR. Lev/s @mqvg; d9.

United States Patent Office 3,321,777 SDFA-BED ASSEMBLY Louis Polrorny, Jr., Ronkonkoma, N.Y., assignor of onethird to Louis Pokorny, Ronkonkoma, N.Y., and onethird to John M. Pokorny, Bellport, NY.

Filed Dec. 1, 1964, Ser. No. 415,050 8 Claims. (Cl. -43) ABSTRACT OF THE DISCLGSURE Collapsible sofa-bed mechanism comprising four sections pivotally interconnected, and sofa body having crosspiece at base of back, and a front board. When collapsed, first section is vertical within sofa back, second section horizontal at bottom of sofa, third section vertical at front of sofa, and fourth section horizontal over second section. Linkage connected between sofa body and point on mechanism other than first section for swinging mechanism out from under crosspiece and over front board. Cradle element fixed to sofa body holds collapsed mechanism, and seat-cushion-supporting membrane covers top of fourth section.

This invention relates generally to sofa-beds, and has particular reference to an improved foldable and refoldable mechanism and an improved mode of association of such an articulated mechanism with a sofa body.

The type of sofa-bed mechanism with which the invention is concerned comprises sections that are pivoted to one another in succession and are foldable between a collapsed sofa position and an extended bed position. The sections include two which lie in superposed horizontal planes when the structure is collapsed and in horizontal alignment when the mechanism is extended; they may be conviently designated upper and lower horizontal sections. Between them, at the front of the sofa, is a front vertical section; and at the rear of the lower horizontal section it is pivotally joined to a rear vertical section, the word vertical signifying that in the collapsed or folded condition of the mechanism these sections lie in substantially vertical planes. Connecting linkages support the mechanism between the opposed side walls of a rigid sofa body which includes a front board and a back structure. The back is usually made hollow to accommodate the rearmost part of the mechanism, including the rear vertical section, when it is in its fully folded condition. The sofa body is usually upholstered and removable seat cushions are supported upon a membrane which overlies the folded mechanism when it is collapsed within the confines of the sofa body. Helping to rigidify the sofa body is a crosspiece extending between the side walls at the base of the back structure at about the level of the seat cushions.

My earlier patents, Nos. 2,832,965 and 3,005,211 show examples of this general kind of assembly. In its extended condition the mechanism stretches forwardly from the sofa body to define four aligned bed-defining sections. A mattress is generally coextensive with the mechanism and foldable and unfoldable with it. The linkage systems described in those patents are of the general type to which the present invention relates; they interconnect the sections in such a way that the mechanism is constrained to fold and unfold in accordance with a predetermined pattern of movement.

It has been common practice in the past to form the front board of the sofa body of two parts, the lower of which is fixed and the upper of which is secured to and moves with the articulated mechanism. Under some circumstances, e.g., for reasons of style, it may be desirable to form the front board as a single rigid unit, having a height substantially equal to that of the mechanism in 3,321,777 Patented l t lay 30, 1967 its fully folded condition, with no part of the front board carried by or movable with the mechanism when it is unfolded to bed position. But the absence of a movable front board section creates several problems, and it is the main objective of this invention to overcome them.

In the first place, since a unitary front board is relatively high (i.e., high with respect to the fixed lower part of one whose upper part moves forwardly with the mechanism when the bed is unfolded) it is a special problem to design the mechanism in such a way that it is capable in a practicable manner of clearing both the rear crosspiece and the front board during the folding and unfolding maneuvers. More specifically, the rearward part of the mechanism must be able to duck under the rear crosspiece and at the same time the forward part of the mechanism must be able to jump over the front board. This calls for new and special linkages and articulations.

Secondly, a relatively high front board requires that the mechanism in its bed position lie at a correspondingly higher-than-usual elevation. As a result, the rear vertical section of the mechanism, which in the conventional device is part of the linkage pivotally connecting the mechanism to the sofa body, is unable to fulfill this function because the upholstered sofa back is in the way. Thus, a special connecting linkage, independent of the rear vertical section, is required.

Other problems, as well, stem from the absence of a movable front board section. One is that no part of the front board can serve either as an anchorage for the seat-cushioning supporting'membrane or as a graspable element to permit the unfolding of the mechanism to be initiated or to control the mechanism during the final moments of the refolding operation. Another is that the centering of the folded mechanism cannot be automatically achieved (as has been possible in the past) by the seating of a movable front board into centered relation to the sides of the sofa frame. Nor is there any longer any automatic limit to the refolding operation, such as that heretofore afforded by the encounter between the movable front board and the fixed front board.

These problems, among others, are resolved by the present invention. An object of the invention is to accomplish this result in a thoroughly practicable manner, whereby the sofa-beds may retain a stylish and trim appearance and yet be manufactured at relatively low cost.

Another objective of the invention is to provide a mechanism and mode of assembly whose manipulation is simple and reliable, which retains equilibrium during the unfolding and refolding maneuvers, and which manifests qualities of sturdiness and reliable functioning over long periods of time.

The preferred way of achieving these objects and the other advantages and benefits hereinafter to be pointed out is illustrated in the accompanying drawings, in which:

FIGURE 1 is a perspective view of an illustrative sofabed assembly embodying the features of this invention, a part of the cushioned seat being omitted to reveal what is beneath;

FIGURE 2 is a side view of the assembly with the near side of the sofa body omitted to reveal the mechanism within it, the mechanism being shown in its fully collapsed sofa-defining condition, and parts of the sofa body being shown only schematically;

FIGURE 3 is a view similar mechanism in a to the sofa body;

FIGURES 4, 5, 6 and 7 are similar views, on a smaller scale, showing successive positions of the mechanism and its component parts during the unfolding procedure;

FIGURE 5a is a fragmentary view of the rear part of the assembly when the unfolding is at the stage depicted in FIGURE 5;

to FIGURE 2, with the partially withdrawn position relative FIGURE 8 is a fragmentary perspective view of the front part of the mechanism in its fully folded condition, showing how it rests upon and is centered by a special cradle element;

FIGURE 8a is a fragmentary view in the same direction as FIGURE 8 showing the cradle element by itself; and

FIGURE 9 is an enlarged detail along the line 9-9 of FIGURE 8.

The sofa body 60 shown in FIGS. 1-5 is schematically depicted because its structural and upholstery features are not material to an understanding of the invention, except for the presence of opposed side walls 11, an upholstered back 10, a crosspiece 61 at the base of the back at about the level of the seat cushions 12, and a one-piece immovable front board 14 extending along the entire length of the sofa. The board 14, as best seen in FIG. 2, has a height about equal to the housed foldable-frame mechanism when in its completely folded condition.

The back 10 of the sofa body is hollow, and affords space for the rearward part of the mechanism, and for its anchorage to the opposed sides 11.

The sofa-bed mechanism comprises four sections pivoted to one another in succession, pivotal articulations between them, and a linkage for mounting the sectional unit in housed condition within the sofa body. In the fully folded condition the sections assume the relative positions shown in FIG. 2. It will be understood that these sections extend for substantially the full length of the sofa from one side 11 to the other, and that the pivotal anchorages of the mechanism to the sofa body are provided in duplicate, one at each side.

In the present mechanism, the sections comprise a rear section 18 pivoted at its lower end 22 (as viewed in FIG. 2) to the lower horizontal section 19. The latter is pivoted at 23 to the front vertical section 20, and the latter is pivoted to the upper horizontal section 21 at 26. (The pivots 23 and 26 are visible only in FIG. 6.) These pivotal connections permit the sections to lie in extended alignment when the mechanism is unfolded to its full extent, thus defining a bed. Each of the bed sections is preferably formed of opposed side rails connected at appropriate regions (as is well known) by braces extending parallel to the front board 14. The side rails are preferably angle members each of which has a horizontal flange and a vertical flange when the mechanism is extended into bed-defining condition. The rear end of the rear section 18 may also be an angle member. The free end of the upper horizontal section 21 preferably consists of a tubular member 62 in the form of a U having short arms.

Extending across the sections in known fashion is a bed spring 63 (see FIG. 1) attached to the opposed horizontal flanges in any suitable manner. It supports a mattress which is coextensive with the mechanism and folds and unfolds with it. (The spring is indicated only in FIG. 1; the mattress is not shown.) In the folded condition of the mechanism the spring and mattress serve to underlie and support the seat cushion 12, in known fashion.

The cushions 12, however, do not rest directly against the spring 63. A membrane 64 is arranged between them, carried by the upper horizontal section 21. One edge of this membrane (which may be a fabric or sheet of any desired kind) is anchored by coil springs 65 (see FIG. 9) to the tubular member 62. To support the opposite edge of the membrane a special angle member 66 is provided adjacent to the articulation 26, and the membrane is secured to it in any suitable way, preferably by providing a rail 67 along the membrane edge (see FIGS. 8 and 9) and riveting the rail, as at 68, to the vertical flange of the member 66.

The member 66 serves another purpose also, in that it affords a graspable element by means of which the unfolding of the mechanism can be initiated. To make it easier to grasp the member 66, the membrane 64 is advantageously provided with suitably reinforced hand holes 69.

The mechanism is mounted in the supporting sofa body (i.e., anchored to the side walls 11) by a linkage which is independent of the rearmost section 18, and engages with the lower horizontal section 19 at the pivot 22. It consists of a relatively long S-shaped link 70 and a pair of shorter links 71 and 72. The link 71 is pivoted to the link 70 at 73 and extends to a fixed pivot 74 on the sofa body. The link 72 is also pivoted to the link 76, but at a point 75 spaced forwardly from the pivot 73. Its other end is pivotally secured to a fixed pivot 76 on the sofa body. The locations of the pivot points 73, 74, 75 and 76, and the lengths of the links 71 and 72, are so chosen that the elongate link 70 is constrained to move between a generally upright disposition behind the crosspiece 61 (FIG. 2) and a generally horizontal disposition curving beneath the crosspiece 61 (FIG. 5a).

The opposite or forward end of the S-shaped link 70 is pivotally secured to the articulation 22. The link is S-shaped so that its rear end will remain behind and beneath the crosspiece 61 during all movements of the mechanism. The link 70 cannot serve as the rearmost bed section because the bed level is above the level of the crosspiece 61 (see FIG. 5a). It is for this reason that the rear bed section 18 is not directly linked to the sofa body as would ordinarily be the case.

Pivoted to the link 70, near its front end, is an actuating link 30. The pivot 28 engages the rear end of the link 30. From a pivot point 78 just forward of the pivot 28 a link 79 extends from the link 30 to the fixed pivot 80 on the bracket 81 secured to the bed section 18. The link 79 is also an actuating link, serving to press rearwardly on the pivot 80 when the mechanism is unfolded (see FIGS. 4 and 5), to swing the section 18 into horizontal alignment with the others to define the bed.

The front end of the actuating link 30 is pivotally connected at 34 to one arm of a lever 35 medially fulcrumed at 36 on the lower horizontal section 19. (The pivot 36 is visible only in FIGS. 6 and 7.) The levers other arm extends from the fulcrum 36 to the pivot A articulating the lever 35 to the rear end of a connecting link 45. The latter is pivoted at 46 to a second lever 40 which is medially fulcrumed at B on a fixed bracket on the front vertical bed section 20. (The fulcrum B is also visible only in FIGS. 6 and 7.)

The second lever 40 is of the bellcrank variety and its forwardly extending arm extends from the fulcrum B to the pivot 42 at which a link 43 is connected. This link extends to the upper horizontal section 21 and is pivoted to it at 44.

The link 45 constitutes a collapsible articulation between the first and second levers 35 and 40. It has an extension 48 beyond the pivot 46 which at some times abuts against the pin or abutment 47 carried by lever 40, and at others it moves away from this pin. The extension 48 rests against the pin 47 during the movements of the collapsed mechanism between the sofa position of FIG. 2 and the intermediate partially withdrawn position of FIG. 3; it moves away from the pin 47 as the mechanism swings between the position of FIG. 3 and the legsupported position of FIG. 5; and it returns to a position of contact with abutment 47 when the mechanism is fully extended (FIG. 7). The link 45 allows the lever 35 to swing counterclockwise from the position of FIG. 2 to that of FIG. 5 without imparting any movement to the lever 40. The significance of this is that the intermediate leg 38 is allowed to jump over the front board 14 and assume an operative support position on the floor (FIG. 5) before any further unfolding of the mechanism (FIGS. 6-7) can be effected. Similarly, during the refolding of the mechanism the parts can be adjusted from the extended condition of FIG. 7 to the compacted condition of FIG. 5 without lifting the leg 38. Thus any instability of the sofa during these maneuvers, tending to topple the entire structure forwardly, is prevented.

The leg 38 is swung between a retracted position beneath the lower horizontal section 19 (FIGS. 23) and its vertical operative position (FIGS. 5-7) by means of an actuating link 82 extending from a pivot 83 on the lever 35 to a pivot 84 on the leg 38. The leg is pivoted at its upper end 85 (visible only in FIG. 7) to the lower horizontal section 19, just rearward of the pivotal connection 23 (FIG. 6) between sections 19 and 20. A caster 39 is preferably provided on the free end of the leg 38.

Before describing the operation of the mechanism, other parts of the linkage system should be described.

The front leg 58, pivoted to the upper horizontal section 21 at 55, is automatically swung between the fully operative position of FIG. 7 and the fully retracted position of FIGS. 2-5 by a link 59 extending from it to the link 43. The link 59 is pivoted to the actuating link 43 at 86 and to the leg 58 at 87.

The angle member 66 at the front end of the upper horizontal section 21 is automatically swung downwardly out of the way by securing each end to a lever arm 88 medially pivoted at 89 to the section 21 (FIG. 6), the arm 88 being pivoted at its rear end 90 to a link 91 extending to the front vertical section 21 and pivoted to the latter at 92. When the sections 25) and 21 are at right angles to each other (FIGS. 2-5 and FIG. 8) the member 66 lies closely adjacent to the axis of articulation 26 between them. As the sections 20 and 21 increase the angularity between them (FIGS. 6-7) the linkage 91 and 88 causes the member 66 to move into the depressed out-of-the-way position shown in FIG. 7. The membrane 64 slackens during this adjustment but remains secured at front and back, respectively, to the member 66 and the end rail 62 of section 21.

The adjustment of the compacted mechanism between the fully housed position of FIG. 2 and the partially extended position of FIG. 5 is facilitated by the elevatorarm 50 and the parts associated with it. The arm 50 is rigidly secured at its lower end, as by rivets 96 (FIG. 2), to a U-shaped cradle element 93 (FIGS. 8 and 8a) extending across the sofa body, near the front, between the side walls 11. The ends of the upturned U arms 95 of the element 93 are pivotally supported by the sofa body at positionally fixed pivot points 51.

The lower end of the elevator arm 50 is pivotally connected at 53 to the front end of a tension bar 99 whose rear end is secured to coiled tension springs 52, the rear ends of the later being anchored to the sofa body at 54!.

The upper end of the elevator arm is pivoted at 94 to a pair of divergent extension links 97 and 98, of which the link 97 extends to the actuating link 30 and is pivoted to it at 190, and the link 98 extends to the lower horizontal section 19 and is pivoted to it at 101.

In the completely housed condition of the mechanism, as shown in FIGS. 2 and 8, the lower ends of the side rails of the front vertical section, and the adjacent part of the lower horizontal section 19, rest upon the cradle element 93. The folded mechanism is centered, and held against wiggling, by upstanding flanges or fingers 102 formed on the element 93 in appropriately spaced locations. The springs 52 are in a tensioned condition pulling rearwardly upon the lower end 53 of the elevator arm 50. The urgence toward swinging the elevator arm 50 upward, i.e., in a clockwise direction as shown in the drawings, is counteracted by the weight of the mechanism. During the initial stages of unfolding movement the springs 52 thus counterbalance this weight and make it easier for the user to lift the mechanism upward and forwardly toward the position of FIG. 3. Similarly, during the refolding operation the springs 52 facilitate the return movement of the parts.

The operation of the mechanism is as follows: After the sofa cushions 12 have been removed, the angle memher 66 is grasped to initiate an upward forward movement of the mechanism as a whole. Aiding in this movement are the springs 52. During the transition from FIG. 2 to FIG. 3 the pivot 73 at the upper or rear end of the S- shaped elongate link 70 is constrained to move in a circular path around the fixed pivot 74; the pivot 75 is constrained to move in a circular are around the fixed pivot 76; and the pivot 94 at the upper end of the elevator arm 50 is constrained to move in a circular are around the fixed pivot 51. There is little change in the general relationship of parts during the movement from the condition of FIG. 2 to that of FIG. 3. It should be noted, however, that the supporting linkage 7d, 71, 72 has guided the rear vertical section 18 downwardly and forwardly beneath the crosspiece 61. At the same time the bundle of parts has been canted upward at the front to a relatively steep angularity which will presently allow the leg 38 to jump over the fixed front board 14 without interference. This elevation of the mechanism is attributable in part to the extension link 97 which is moving into alignment with the elevator arm 50 and affording a temporar-y added length to the latter.

As the elevator arm continues its clockwise movement (FIGS. 4 and 5) the actuating link 30 is caused to move rearward with respect to the section 19, and the effect of this is to press rearwardly upon the link 79 thereby bringing the rear section 18 downward into alignment with the section 19. Also activated by the link 30 is the lever 35 which is moved in a counter-clockwise direction thereby compelling the leg 38 to swing downward to the operative position shown in FIG. 5. During this period, the rotative movement of lever 35 is ineffective to bring about any swinging movement of the lever 49, as a result of which the sections 19, 20 and 21 of the mechanism remain in the compacted condtion of FIG. 5 until a lifting force is applied to the upper horizontal section 21. A rotation of this section through the position of FIG. 6 to that of FIG. 7 brings about an alignment of all the bed-defining sections, lowers the front leg 58, and swings the member 66 out of the way.

The abutment between the link extension 43 on link 45 and the pin or stop 47 on lever 40 in the fully folded and fully unfolded condtions serves to prevent the levers 35 and 40 from moving beyond the ranges prescribed for them.

The operation takes place in reverse during the refolding of the mechanism. The sections 21 and 20 are first restored to the relationship shown in FIG. 5, and during this maneuver the connecting link 45 is ineffective to transmit any movement to lever 35 as a result of which the leg 38 remains in the operative propping position. Thus support is afforded until the parts have passed through the inherently unstable condtions of FIG. 6 and reached the safer relationship of FIG. 5. Then the compacted parts can be safely lifted into and through the postures of FIGS. 4 and 3 and ultimately restored to the fully housed condition. During this adjustment the leg 38 jumps clear of the front board, and the mechanism ducks under the crosspiece 6 1 ultimately bringing the supporting linkage and the rear bed section 18 into the upright disposition within the hollow back structure 10. As the mechanism reaches its housed state it slips snugly into centered and supported relation to the waiting cradle element 93.

The invention thus affords a sofa-bed assembly in which the style requirements of a fully upholstered permanent sofa back, and an uninterrupted unitary front board, can be complied with in a practicable economically feasible manner and without sacrifice of simplicity, reliability, ease of manipulation, or comfort in either the sofa or the bed condition of the device.

It will be understood that many of the details shown may be modified by those skilled in the art without necessarily departing from the spirit and scope of the invention as expressed in the appended claims.

What is claimed is:

1. In a sofa-bed assembly, a sofa body having a hollow back, a crosspiece at the base of the back, sides, and a front board whose top edge is approximately at the level of said crosspiece; a mechanism formed of pivoted sections including in succession a rear section, a lower horizontal section, a front vertical section, and an upper horizontal section, said sections being foldable between (a) a collapsed sofa position in which the horizontal sections lie in superposed relation while the rear section is within said back and (b) an extended bed position in which said sections extend in horizontal alignment forwardly from in front of the back and across said front board; and a supporting linkage independent of said rear section and directly connected to the rear of said lower horizontal section for pivotally connecting said mechanism to said sofa body.

2. A sofa-bed assembly as set forth in claim 1, in which said supporting linkage comprises an elongate link mounted for movement between an upright disposition behind said crosspiece and a substantially horizontal disposition beneath said crosspiece, the rear region of said link being articulated to the sofa body within said hollow back, the forward end being pivoted to said mechanism at the rear of said lower horizontal section.

3. A sofa-bed assembly as set forth in claim 2, in which said linkage includes a pair of shorter links each of which is pivoted at one end to the rear region of said elongate link and at the other end to the sofa body, said elongate link being S-shaped and movable by said shorter links between said upright and horizontal dispositions.

4. A sofa-bed assembly as set forth in claim 2, said elongate link being pivoted at its forward end to the pivot between said rear section and said lower horizontal section.

5. In a sofa-bed assembly, a sofa body having a hollow back, a crosspiece at the base of the back, sides, and a front board whose top edge is approximately at the level of said crosspiece; a mechanism formed of pivoted sections including in succession a rear section, a lower horizontal section, a front vertical section, and an upper horizontal section, said sections being foldable between (a) a collapsed sofa position in which the horizontal sections lie in superposed relation while the rear section is within said back and (-b) an extended bed position in which said sections extend in horizontal alignment forwardly from in front of the back and across said front board; a supporting linkage independent of said rear section for pivotally connecting said mechanism to said sofa body within said hollow back, said supporting linkage comprising an elongate link mounted for movement between an upright disposition behind said cross piece and a substantially horizontal disposition beneath said crosspiece, the rear region of said link being articulated to the sofa body within said hollow back, the forward end being pivoted to the pivot between said rear section and said lower horizontal section, and said mechanism including an activating link extending forwardly from a point on said elongate link adjacent to and rearward from said pivoted forward end, and linkage between said activating link and said rear section for bringing the latter into alignment with said horizontal section when the mechanism is extended.

6. In a sofa-bed assembly, a sofa body having a hollow back, a crosspiece at the base of the back, sides, and a front board whose top edge is approximately at the level of said crosspiece; a mechanism formed of pivoted sections including in succession a rear section, a lower horizontal section, a front vertical section, and an upper horizontal section, said sections being foldable between (a) a collapsed sofa position in which the horizontal sections lie in superposed relation while the rear section is within said back and (b) an extended bed position in which said sections extend in horizontal alignment forwardly from in front of the back and across said front board, a supporting linkage independent of said rear section for pivotally connecting said mechanism to said sofa body within said hollow back, a transverse cradle element in the sofa body behind the lower region of said front board, and upstanding space-d locating fingers on said cradle element adapted to engage and center the mechanism when it is housed in said sofa body behind said front board.

7. In a sofa-bed assembly, a sofa body having a hollow back, a crosspiece at the base of the back, sides, and a front board whose top edge is approximately at the level of said crosspiece; a mechanism formed of pivoted sections including in succession a rear section, a lower horizontal section, a front vertical section, and an upper horizontal section, said sections being foldable between (a) a collapsed sofa position in which the horizontal sections lie in superposed relation while the rear section is within said back and (b) an extended bed position in which said sections extend in horizontal alignment forwardly from in front of the back and across said front board; a supporting linkage independent of said rear section for pivotally connecting said mechanism to said sofa body within said hollow back, a transverse member independent of said front board adjacent to the pivot between said front vertical section and said upper horizontal section, a seat-cushion-supporting membrane anchored to said transverse member, and means for moving said transverse member downward to an out-of-the-way position when said front vertical section and upper horizontal section move into horizontal alignment, said means comprising a lever pivoted to said upper horizontal section and secured to said transverse member, and an actuating link pivoted at one point to said front vertical section and at another point to said lever.

8. A sofa-bed assembly as set forth in claim 6, in which said cradle element is pivotally supported at its ends to said sofa body, and in which the mechanism includes an elevator-arm having one end rigidly secured to said cradle element and its other end articulated to the lower horizontal section, the locating fingers on the cradle element extending upwardly when the mechanism is in the sofa body in its collapsed sofa position.

References Cited UNITED STATES PATENTS 2,749,559 6/1956 Petersen 5-13 3,165,757 1/1965 Rogers 5-l3 3,173,154 3/1965 Katz 5-13 3,209,378 10/1965 Laemmle 5-13 3,247,526 4/1966 Rogers 513 CASMIR A. NUNBERG, Primary Examiner.

Notice of Adverse Decision in Interference In Interference No. 96,297 involvi Patent No. 3,321,777, L. Pokorny, J r., SOFA-BED ASSEMBLY, final ju gment, adverse to the patentee was rendered Aug. 20, 1968, as to claims 1, 2, 4 and 5.

[Oyficz'al Gazette October .Q9, 1968.] 

1. IN A SOFA-BED ASSEMBLY, A SOFA BODY HAVING A HOLLOW BACK, A CROSSPIECE AT THE BASE OF THE BACK, SIDES, AND A FRONT BOARD WHOSE TOP EDGE IS APPROXIMATELY AT THE LEVEL OF SAID CROSSPIECE; A MECHANISM FORMED OF PIVOTED SECTIONS INCLUDING IN SUCCESSION A REAR SECTION, A LOWER HORIZONTAL SECTION, A FRONT VERTICAL SECTION, AND AN UPPER HORIZONTAL SECTION, SAID SECTIONS BEING FOLDABLE BETWEEN (A) A COLLAPSED SOFA POSITION IN WHICH THE HORIZONTAL SECTIONS LIE IN SUPERPOSED RELATION WHILE THE REAR SECTION IS WITHIN SAID BACK AND (B) AN EXTENDED BED POSITION IN WHICH SAID SECTIONS EXTEND IN HORIZONTAL ALIGNMENT FORWARDLY FROM IN FRONT OF THE BACK AND ACROSS SAID FRONT BOARD; AND A SUPPORTING LINKAGE INDEPENDENT OF SAID REAR SECTION AND DIRECTLY CONNECTED TO THE REAR OF SAID LOWER HORIZONTAL SECTION FOR PIVOTALLY CONNECTING SAID MECHANISM TO SAID SOFA BODY 